1. Technical Field
The embodiments generally relate to the field of in vitro diagnostics, and more particularly to lateral flow assays to detect analytes.
2. Description of the Related Art
Traditional lateral flow assays, such as “strip” or “dip stick” tests are used for a large number of diagnostics applications. The test membranes may include, but are not limited to, glass, glass fiber, silicone, plastic, paper, aluminum foil, or other porous cellulose and rayon compounds that may be hydrophilic or hydrophobic. Specific lines or zones are “striped” onto or applied to the membrane that contain certain chemical capturing reagents or compounds, designed to react and bind with predefined biological markers which may be present in test sample fluids such as, but not limited to, sputum, urine, blood, water, liquefied food samples, concentrated and liquefied air samples and surface swabbed samples.
When one end of a striped assay is dipped into the sample fluid to be tested, the sample fluid is drawn by capillary action along the longitudinal axis of the membrane analyte assay strip. As target proteins, enzymes or bio-markers migrate along a membrane assay strip, they interact with the striped chemical capturing reagents, producing measurable and detectable changes along striped analyte assay test zone sites. The resulting detectable and measurable changes at striped zones can be due, but not limited to, binding with colloidal gold, latex dyed beads, charcoal beads, or magnetic or paramagnetic beads and particles capable of emitting luminescence, fluorescence, auto-fluorescence, phosphorescence, or chemiluminescence indicia. Often, a quality control analyte assay test binding stripe is co-located within the membrane analyte assay test strip, and is designed to react with a test sample fluid to form at least one detectable and measurable band, indicating the validity and the completion of the analyte assay test.
Strip test technology is well known in the art and includes immunodiagnostic, enzymatic, lateral flow immunochromatography, and related chemistries. Analyte assays employing this technology include pregnancy tests, U.S. Pat. No. 5,602,040 issued to May et al., and an apparatus for performing simultaneous single tests on multiple strips for detecting multiple drugs of abuse, U.S. Pat. No. 5,976,895 issued to Cipkowski, the complete disclosures of which, in their entireties, are herein incorporated by reference.
Methods to imbed strip tests, such as those described above, into machine readable barcodes have been described in U.S. Pat. No. 6,770,487 issued to Crosby and U.S. Patent Publication No. 2009/0020609 published to Cohen et al., the complete disclosures of which, in their entireties, are herein incorporated by reference. Rendering the strip test as a barcode enables simultaneous reading and identification of the data associated with the sample itself as well as the test type, validity, date, location, and results. These data can be conveyed directly to authorized individuals or medical personnel and stored in databases for later prognostics, queries, verification, and archival purposes. Imbedding immunodiagnostic tests into barcodes overcomes problems associated with manual entry of test takers, test type, test parameters, and test results. Manual entry is not only costly, but also introduces an opportunity for errors or loss of test data altogether, which, in the case of diagnostic tests, may compromise patients' safety and clinical outcomes, and in the case of food safety testing, may compromise the quality and safety of the food supply and derivative products posing great risk to public health as well as incurring significant economic costs.